Improvement in rock-drills



I UNITED STATES 'and Stateof New York, have invented a new Y tons so constructed as to exhaust the steam f Eating device so constructed that it may be fm the loose ring and adjustable 'stationary' fully described.;

proved drill.

idrill as it makes its up stroke.

- equivalent, in combination with the piston of a rock-drill; and in an improved chuck for.

parts to hold the drill-bit by a strap or clip,.-

GEOEGE E. NUr'rI-NG AND JOSEPH A, li-iJrENr OFFICE.' g

o. GITHENs, 0E NEW YoEir, wir,

ASSIGNORS fil() A; (l. RAND, O F SAME PLACE.

speeieatibntforming part of Letters Patent No. 140,637, dated .iuiy'e,`1va;applicati@ mee June' 30, 18,73.

I'o all 'whom it may concern: v e

Y Be it known that we, GEORGE E. N UTTING and-JOSEPH C. GITHENS, of. the city, county and useful Improvement in Rock-Drill, of which the following is a specification: Figure l is a longitudinal section of our im- Fig. 2 is a detail section taken; through the line a' x, Fig. 1. Similarletters of reference indicate correspending parts. y

'Our invention has for its object to furnish 'hich thepiston may turn, and thus turn the .The invention consists in the combination, v :.th the slidevalve of a steam rockdrill,of pis-v rom the end parts of the steam-chest in front said valve and pistons; in the combination, with the piston of a steam rock-drill, of a roheld to its work by friction, and may yield .2h01 -ld the drill-bit be prevented from turning;

friction-strap, andthe pawl' and ratchet, or

rock-drill bits, formed by dividing the hollowr forward end of the pistonrod longitudinally into -three or-more` parts, andcontracting said openupon one or both sides, as hereinafter A isY the steam-cylinder. B is' the piston which moves up and down in the cylinder A, and the rod C, which passes out through a stuing-box at the lower end of the cylinder A. To the lower end of the pistou-rod C is secured by a suitable coupling, D, the drillbit or cutting-tool E. `F is. the steam-chest, from the middle parts of which the ports G lead into the `cylinder A at or near its ends. l1 is the port through which -the steam exhausts. I is the valve, by the `movements of which-.the ports are opened and clos-ed. J is the valve-stem,- which passes through and slides in "the valve I, and` the end parts of which -slide in stuing-boxes in the ends of the `stpjeam-chest F. To the end parts of the valve-ste`m J are. rigidly attached two disks,` K, at a'dstance apart equal to the `dista-nce required `or the throw of the valve I, and an additional thirty-secondof an inch, more or less. Upon the stem J, upon each side of the valve I, are placed pistons, L, of such a .size as to work steam-tight in the end parts of the steam-chest F, and ofsuch a length as to give the valve I and two pistons K a play of about a thirty-second of an inch upon the g stem J', between .the disks K. The Adiameter' of the disks K is made enough less #th/an the diameter ofthe end parts ot' the valve-chest to allow the steam to pass the said disks freely. In the end parts of. the pistons L are formed ring-grooves-M, from whichy holes m lead out through -t-he ends of said pistons, as shown' in Fig. 1. N are exhaust-ports leading out from the end parts of the steam-chest to the openair. Bythis construction', 'as the piston B comes into the A.position shown in Fig. l, the lower port() is uncovered and the steampasses through it into' the lower end of the steam-chest F, below lthe lower disk K. As the steam enters thelower part of the steam-chestF it forces the disks K, pistons L,

valve I, and -valve-stem J upward until the upper disk K strikes its stop and stops the forward movement ofthe ystem J and disks K.

Thesteam nowpasses aru-nd the edge ofthe :lower disk' Kf. and forces the pistons L and valve I upward until stopped by the upper disk K. This movement allows the steam in the end part ofthe steam-chest F to exhaust through the the exhaust N. The exhausts N are so arranged as not to be fully closed until the valvelpistons and disks have nearly completed their stroke.' By `this construction the valve I .and its attachments and the piston B will always move in the same direction, which lessens the jar, and consequently the wear, of the mechanism.. It will lbefohserved that by arranging the exhausts 0 the piston B and valve I and its attachments may be .cushioned with steam atA one or beth ends of their stroke, and to any desired extent. l? is an angular spiral or twisted rod,

' which is swiveled to the upper head of the cyl-' 'inder A, andwhich passes through a guidenut, Q, secured in the upper end of the piston B. Tc the outer end of the rod P is attached ajratchet-Wheel, R, upon the teeth of which thel pawl S takes hold. The pawl S is placed ni" a ring, T, and is held forward against the ratchet-wheel by a spring. The vring T surrounds the ratchet-Wheel R., and "is in turn surrounded by the friction-strap U,Whichlis rigidly connected With-the cylinder-head. The

- three or more parts, which. parts are pressed together to clasp the' drill-bit E by a strap or clip, W, which is made open upon one orboth sides,.and the'ends of which are secured by bolts, so that the drill-bit E may be securely held and may be conveniently detached when desired.

Heretofore chucks for rock-drills have been made with two longitudinal slots extending the length of the bore, but the continual percussion and strains upon the drill-bar Wear an oblong hole in the end of the chuck, causing much trouble and uncertainty in the direction of the blow given.

By dividing the chuck into three longitudinal slots, and surrounding it with a strap, We

--bring the-pressure to bear equally from all dif rect-ions, the bar is kept straight, and any wear taken up by tightening the strap.

Having thus described cur inventicn, irc claim as new and desire tc secure by Letters Patentl. The combination, 'with the valve l, ci pistons L and port N, constructed substantially as described, so as to exhaust the steam, frein the end of the 'stcarn-chcstvF inte the main exhaust, or directly to' the atrnsphegce, as. shown. f

2. Thecombinaticn, with the piston a steam rock-drill, et a rotating device, si stantially such as is herein described, so it may be held to its work by friction, and

lmay yield should the drill-bit be prevented from turning.

3. The loose ring and adjustable stationary friction-strap and pawl and ratchet, or equivalent, with the piston of a rock-drill, substantially as herein shown and described.

' 4. An improved chuck for rock-drill bits,

formed by dividing the hollow forwand end of the piston-rod C longitudinally into three drmore parts, and contracting said parts to hold the drill-bit by a strap lor clip, open upon one or both sides, substantially as herein shown and described.

v5. The valve mechanism, substantially as described, consisting ofl the piston-Valves L,

disks K, valve'l, a'ndports N, as and fon the purposes specified.

GEO. E. NUTTING;

JOSEPH C.'C`rlTHENS.

Witnesses:

T. B. Mosman, JAMES T. GRAHAM. 

